The Union City operator of a bogus charitable organization that was used by some of the defendants in the biggest corruption sting in New Jersey history pleaded guilty yesterday to tax evasion and operating an unchartered bank, federal authorities said.

Moshe “David” Schwartz, 33, admitted that he ran the Gemach Shefa Chaim as a bank, accepting millions in deposits — including nearly $1 million of his own money — that he hid from state and federal regulators.

Schwartz, who appeared before Judge Jose Linares, faces up to five years in prison on the banking offense and up to three years in prison on the tax offense, the U.S. Attorney’s Office said. Each offense also carries a fine of up to $250,000. Schwartz is scheduled to be sentenced on July 30.

The Gemach Shefa Chaim charity was purportedly created to provide interest-free loans to needy members of the Sanz community in Union City, officials said. During his guilty plea proceeding, Schwartz admitted he operated GSC as a bank, with more than 350 client accounts by July 2009.

In July 2009, the charity was caught up in the Operation Bid Rig III corruption sting when more than 40 public officials and others were charged, most of them with giving or accepting bribes to expedite fictional development projects promoted by government informant Solomon Dwek.

Moshe Altman, 44, Itzak Friedlander, 46, and Shimon Haber, 38, used GSC accounts to launder proceeds that Dwek had purported to be the proceeds of illegal activities.

Altman pleaded guilty in December 2010, to, among other things, conspiring to launder monetary instruments and was sentenced in March 2011 to 3½ years in prison. Friedlander pleaded guilty in April 2010 to conspiracy to launder monetary instruments and was sentenced in April 2011 to two years in prison.

Haber pleaded guilty to the same charge in January 2010 and was sentenced in May 2010 to five months in prison. Haber admitted conspiring with Altman and Friedlander to accept funds from Dwek and using the GSC charity to funnel the funds to a Union City official in exchange for development approvals for a project Haber and Dwek were partners in.

Campaign finance reports on file with the state Election Law Enforcement Commission show a $2,500 donation on May 8, 2007, from David Schwartz, of Gemach Shefa Chaim, to Brian Stack’s senatorial campaign fund. A spokesman for said the state senator, who is also the Union City mayor, said Stack donated the contribution to a domestic violence shelter in the fall after learning through media reports the funds might be tainted.

In his guilty plea, Schwartz admitted to opening accounts at other banks across North Jersey in the charity’s name and depositing clients’ funds into those accounts. By doing this, many GSC clients were able to use their accounts to engage in suspicious and, at times, illegal activities, including evading federal taxes and money laundering, authorities said.

To operate, a bank is required to obtain a charter from the United States or the state in which the bank operates. Chartered banks are subject to oversight, regulation, and periodic review by federal and state authorities. Schwartz and the GSC never obtained a charter.

Schwartz also admitted that he provided fraudulent information to his tax preparer in Union City concerning his 2007 income, reporting his income as $24,475 when it was approximately $208,845. Schwartz admitted that he used his own GSC account and a false identity to conceal his income and assets from the IRS, causing a $74,889 tax loss.